Technical Field
The present disclosure generally relates to resistive change elements and arrays of resistive change elements and, more specifically, to scaling resistive change elements to smaller dimensions.
Discussion Of Related Art
Any discussion of the related art throughout this specification should in no way be considered as an admission that such art is widely known or forms part of the common general knowledge in the field.
Resistive change elements and arrays of resistive change elements are used in a variety of devices such as memory devices, routing devices, logic devices, sensor devices, and analog circuits. For example, resistive change elements and arrays of resistive change elements can be used to form nonvolatile storage portions of standalone memories and nonvolatile storage portions of embedded memories. For example, resistive change elements and arrays of resistive change elements can be used to form switch matrixes of routing devices.
Resistive change elements include a resistive change material that can be adjusted between at least two non-volatile resistive states in response to an applied stimulus. For example, resistive states within a resistive change element can correspond to data values which can be programmed and read back by supporting circuitry within the device or array. For example, resistive states within a resistive change element can correspond to an ON state or an OFF state for routing signals within the device or array.
For example, a resistive change element might be arranged to switch between two resistive states: a low resistive state (which might correspond to a logic 1) and a high resistive state (which might correspond to a logic 0). In this way, a resistive change element can be used to store one binary digit (bit) of data. Or, as another example, a resistive change element might be arranged to switch between four resistive states, so as to store two bits of data. Or a resistive change element might be arranged to switch between eight resistive states, so as to store three bits of data. Or a resistive change element might be arranged to switch between 2″ resistive states, so as to store n bits of data.
The increasing demand for memory storage capacity and the continuing miniaturization of electronic devices requires resistive change elements scaled to smaller dimensions. Scaling resistive change elements to smaller dimensions requires fabrication methods that reduce the dimensions of the resistive change elements without substantially impacting the desired switching characteristics of the resistive change elements. Fabrication methods designed for resistive change elements with larger dimensions can create overlapping regions that do not substantially impact the desired switching characteristics of the resistive change elements with larger dimensions because the resistive change elements with larger dimensions are less sensitive to overlapping regions. However, when fabrication methods designed for resistive change elements with larger dimensions are used to fabricate resistive change elements with smaller dimensions, overlapping regions that do not substantially impact the desired switching characteristics of resistive change elements with large dimensions can have a substantial impact on the desired switching characteristics of the resistive change elements with smaller dimensions because the resistive change elements with smaller dimensions are more sensitive to overlapping regions.